Vulnerable in New York, or Apparently Secure - Vulnerable to disappearing from New York (but not currently imperiled), with relatively few populations or locations, few individuals, and/or restricted range; or uncommon but not rare in New York; may be rare in some parts of the state; possibly some cause for long-term concern due to declines or other factors. More information is needed to assign either S3 or S4.

Global Conservation Status Rank

G5

Secure globally - Common in the world; widespread and abundant (but may be rare in some parts of its range).

Contents

Summary

Did you know?

Walking on mudflats can be challenging and in some cases even dangerous. It is very easy to sink up to your waist in the soft mud, unless you wear "mudders." Mudder shoes have expandable wings on the side to provide support when crossing mudflats. Worn over boots or waders, the wings expand as you step onto soft surfaces to increase boot area by four times and then retract when you lift your foot.

Conservation and Management

Conservation Overview

Remove shoreline armoring to increase overland sediment input; improve water quality by reducing or eliminating sewer and stormwater discharge and pesticide application; restore tidal regime by removing culverts, dikes, and impoundments, plugging ditches, and replacing static flow restriction devices with those that are calibrated for local tidal hydrology. Ensure connectivity between the open saltwater and low salt marsh.

Conservation Strategies and Management Practices

Remove shoreline armoring to increase overland sediment input; improve water quality by reducing or eliminating sewer and stormwater discharge and pesticide application; restore tidal regime by removing culverts, dikes, and impoundments, plugging ditches, and replacing static flow restriction devices with those that are calibrated for local tidal hydrology. Restoration and monitoring protocols are available (Niedowski 2000).

Development and Mitigation Considerations

Strive to minimize or eliminate hardened shorelines and maintain low-sloped shorelines within the tidal zone to increase overland sediment input. Maintain functional connectivity between the open ocean and bays with salt marsh complexes to enable full tidal flushing during each tidal cycle. For example, barriers such as railway causeways should have numerous culverts to allow sufficient hydrologic connectivity. If flow restriction devices are needed, those that are calibrated for local tidal hydrology can be used. Avoid dumping dredge spoil onto mudflats and low salt marshes. This community is best protected as part of a large salt marsh complex. Protected areas should encompass the full mosaic of low salt marsh, high salt marsh, marine intertidal mudflats, saltwater tidal creek, salt panne, and salt shrub communities to allow dynamic ecological processes (sedimentation, erosion, tidal flushing, and nutrient cycling) to continue. Connectivity to brackish and freshwater tidal communities, upland beaches and dunes, and to shallow offshore communities should be maintained. Connectivity between these habitats is important not only for nutrient flow and seed dispersal, but also for animals that move between them seasonally. Development of site conservation plans that identify wetland threats and their sources and provide management and protection recommendations would ensure their long-term viability.

Rare Species

Range

Global Distribution

None

Best Places to See

Great South Bay (Nassau, Suffolk Counties)

Gateway National Recreation Area (Queens County)

Identification Comments

General Description

The marine intertidal mudflats community is located in quiet waters, with substrates composed of silt or sand that is rich in organic matter and poorly drained at low tide. This community is almost completely unvegetated. Cordgrass (Spartina alterniflora) can occur sporadically, colonizing from adjacent low salt marsh communities. The marine alga sea lettuce (Ulva lactuca) can cover 40% or more of the exposed substrate.

Characters Most Useful for Identification

This intertidal community is almost completely unvegetated on exposed mudflats adjacent to low salt marshes and saltwater tidal creeks where the salinity is greater than 18 ppt. This community is submerged during high tide, and exposed at low tide.

Best Time to See

Marine intertidal mudflats are viewable year round, but are best viewed at low tide from a distance on firm ground or a boat.

Classification

International Vegetation Classification Associations

This New York natural community encompasses all or part of the
concept of the following International Vegetation Classification (IVC)
natural community associations. These are often described at finer
resolution than New York's natural communities. The IVC is developed and
maintained by NatureServe.

Similar Ecological Communities

Low salt marshes and marine intertidal mudflats are often adjacent to each other, or can form a patchy mosaic within an embayment. Both communities are influenced by diurnal tides and often have similar muddy substrates. However, marine intertidal mudflats are almost completely unvegetated compared to low salt marshes that have diverse and often dense vegetation cover dominated by cordgrass (Spartina alterniflora).

Both communities are intertidal and essentially unvegetated. However, marine intertidal mudflat substrates are composed of silt or sand that is rich in organic matter and poorly drained at low tide. Mudflats are usually adjacent to low salt marshes and saltwater tidal creeks. Whereas, marine intertidal gravel/sand beaches are composed of sand or gravel substrates that are well-drained at low tide; and they are usually adjacent to maritime beaches.

Unlike marine rocky intertidal communities, which have high-energy wave action and rocky substrates, marine intertidal mudflats are characterized by quiet waters and unconsolidated soils. Marine intertidal mudflats occur on fine silt or sand that is rich in organic material. They are exposed at low tide, and have a diverse array of invertebrates that provide important fuel for migrating and breeding shorebirds.

Marine intertidal mudflat substrates are composed of silt or sand that is rich in organic matter and poorly drained at low tide. Mudflats are usually adjacent to low salt marshes and saltwater tidal creeks. Whereas, maritime beaches are terrestrial and are located above the high tide line. Maritime beaches are usually adjacent to marine intertidal gravel/sand beaches offshore and maritime dunes or bluffs landward.

Saltwater tidal creeks and marine intertidal mudflats are often adjacent to each other within a salt marsh complex. Both communities are influenced by diurnal tides and often have similar muddy substrates. However, marine intertidal mudflats are submerged during high tide, and exposed at low tide, whereas saltwater tidal creeks have a permanently flooded subtidal channel.

Vegetation

Herbs

1%

Nonvascular plants

40%

Unvegetated

100%

Percent cover

This figure helps visualize the structure and "look" or "feel" of a
typical Marine Intertidal Mudflats. Each bar represents the amount of
"coverage" for all the species growing at that height. Because layers
overlap (shrubs may grow under trees, for example), the shaded regions
can add up to more than 100%.